This section is intended to introduce various aspects of the art, which may be associated with exemplary embodiments of the present techniques. This discussion is believed to assist in providing a framework to facilitate a better understanding of particular aspects of the present techniques. Accordingly, it should be understood that this section should be read in this light, and not necessarily as admissions of prior art.
A conventional gas turbine engine often has a turbine compressor that is mechanically linked to an expander turbine through a shaft. The turbine compressor can be used to compress a flow of air ingested by the turbine compressor. The compressed air is then flowed to a combustor. In the combustor, fuel is injected and ignited to create a continuous flame. The high pressure exhaust gases from the flame are flowed into the expander turbine, which generates mechanical energy from the exhaust gas as it expands.
The exhaust gas may include a mixture of nitrogen (N2), carbon dioxide (CO2), water (H2O), and any number of other gaseous components. In some cases, it may be desirable to remove at least a portion of the CO2 from the exhaust gas as a CO2 product. According to current techniques, solvent based separation processes, amine processes, pressure swing adsorption processes, or the like are used to recover the desired CO2 product. However, the CO2 product that is recovered using such processes is at a low pressure and must be compressed as a gas to a high pressure for use in enhanced oil recovery (EOR) or carbon storage applications.
One technique for removing CO2 from the flue gas of a power station is described in U.S. Patent Application Publication No. 2011/0226010 by Baxter. Moisture is removed from the flue gas to yield a dried flue gas, and the dried flue gas is compressed to yield a compressed flue gas. The temperature of the compressed flue gas is then decreased using a first heat exchanger and a second heat exchanger. At least a portion of the CO2 within the compressed flue gas condenses within the first and second heat exchangers, yielding a solid or liquid condensed-phase CO2 component and a light-gas component. The condensed-phase CO2 component can then be recovered. However, recovering the CO2 product from the flue gas using such techniques may be costly due to the high degree of compression that is required.